The invention relates to a spring-loaded, locking press pin.
Such a press pin is for example known from patent DE 93 19 800 U1, assigned to the assignee of the present application.
The press pin shown there has the advantage that it exhibits a lock on the inside between the guide sleeve and the spindle-shaped button. This button can be rotated and moved and is spring-loaded on the guide sleeve. Such covered locking devices have the advantage that they are insensitive to external dirt. The retainer area is arranged radially outward of the shown covered locking device, between the spindle-shaped button and the guide sleeve, extending in the axial direction. This however results in the disadvantage that the outside diameter of the press pin becomes very large, because the locking device and the spring arrangement are arranged in a radial successive configuration.
The task of the invention is therefore to further improve a press pin of the kind initially specified so that it has a small outside diameter while preserving the advantages of a covered locking device.
The advantages according to the invention arise as a result of the combination of the three features indicated in the characteristics. The first feature describes the covered locking device, which has the advantage that a ring recess is provided in the spindle-shaped button, which is at least partly open downwards in axial direction, resulting in particularly easy assembly possibilities.
The second feature of the invention has likewise the purpose of easy assembly, because the pressure spring is arranged in a downwards open borehole of the guide sleeve and is only supported at a corresponding shoulder of the retracted pin, with the shoulder having a larger diameter. This thereby simplifies the assembly substantially.
Finally the final feature has the advantage that it describes the axial successive configuration of the covered locking device and the spring arrangement, what altogether results in a smaller outer circumference of the press pin.
The variation from the present state of art with a radial successive configuration of an interior locking device and an external spring arrangement is that the invention arranges these two functional elements either in successive axial direction or underneath each other, so that the axial length of the press pin becomes somewhat longer than the well-known press pin, but the outer circumference of the press pin is substantially decreased.
Therefore besides the smaller outside diameter, an easy assembly is achieved as well.
In a preferred embodiment of the invention the ring recesses are created by two sleeve elements of the spindle-shaped button. These ring recesses are located in the spindle-shaped button and retain the locking teeth of the guide sleeve.
Therefore these ring recess can be placed very close to the outer circumference of the spindle-shaped button, whereby good retaining forces for the locking device result.
The external sleeve element, covering the locking device, can therefore be narrow.
In a further embodiment the internal and external sleeve element are connected to each other in the bottom part of the button by radial connection fins in at least two places opposite each other.
Thus a superior stability of the button, which is usually made of plastic, results, because despite the ring recess being placed close to the outer circumference, an excellent stability of the ring recess for engaging the locking teeth of the guide sleeve is ensured.
The formation of the connection fins in the bottom part of this ring recess closes this ring recessxe2x80x94with the use of two locking teethxe2x80x94in two places opposite each other through corresponding connection fins, so that the connection fin makes a connection between the external and the internal sleeve element of the button. Thus the two sleeve parts are protected against distortion, the ring recess is altogether mechanically highly stable under load and can tolerate bending moments, even if the button is actuated when it is tilted in an angle to its longitudinal axis towards the engaging guide sleeve.
A further advantage results from the successive configuration of locking device and spring arrangement due to the fact that now large spring-loaded strokes of the press pin are possible because of the separate arrangement of the spring from the locking device.
Thus the axial length of the chamber containing the pressure pin can be very long, results in the advantage that the press pin can exhibit a large stroke, because even with large strokes a stable and distortion protected ring recess is created in the button, due to the formation of connection fins between the external and the internal sleeve element.
A particularly favorable assembly arises as a result of the fact that the pin on the inside exhibits an axial stud, which is equipped with a barb-hook-like mounting profile. This mounting profile engages with barb-hook-like projections into the bore wall of the longitudinal borehole in the button.
For the assembly thereof the button, manufactured usually from plastic, is simply put with its longitudinal borehole on the face of the mounting profile of the pin and hit with the hand, whereby the pin with its mounting profile digs itself into the inner walls of the bore in the button and becomes inseparably connected with the pin. Thus no connection by means of retainer rings is required, as they were required for example in DE93 19800U1.